Slash pine tree named ‘CF PS1-3352’

ABSTRACT

A new and distinctive variety of a slash pine tree which has been denominated varietally as ‘CF PS1-3352’ which is distinguished by high growth rate, good resistance to fusiform rust and pitch canker, excellent stem straightness, medium crown width, long stem internodes, flat to medium branch angle and medium branch diameter.

Latin name: Pinus elliottii.

Variety denomination: ‘CF PS1-3352’.

BACKGROUND

A new variety of slash pine tree (Pinus elliottii Engelm.) has been discovered. This selection has been designated as ‘CF PS1-3352.’

This new variety is a progeny of two first generation selections. Female parent is a first generation selection made in Taylor County, Fla. Male parent is a first generation selection made in Wayne County, Ga.

Cross pollination occurred in early 1998 followed by induction and cryopreservation of embryogenic tissue in 1999. First somatic seedlings were produced in 2000 and planted in early 2001 in three field experiments. A total of 15 ramets were planted at 5 ramets per field experiment. The field experiments are located in Florida and Georgia.

BRIEF SUMMARY

A new and distinct cultivar of slash pine (Pinus elliottii) is distinctly characterized by high growth rate, good resistance to fusiform rust and pitch canker, excellent stem straightness, medium crown width, long stem internodes, flat to medium branch angle, medium branch diameter and which is mature for commercial harvesting sooner than conventionally grown trees under the ecological conditions prevailing the Atlantic and Gulf Coastal Plains of the United States.

The Pinus elliottii plants of this variety were asexually propagated using an advanced form of micropropagation called somatic embryogenesis carried out at a production facility in Victoria, Canada. Somatic embryogenesis uses a complex process which relies on the splitting of one embryo into many identical embryos. Somatic embryos can then be grown into plants which are all identical genetically. The asexual propagation occurs at an earlier stage in the plant's life cycle than most other micropropagated plants. The detailed methods for somatic embryogenesis used for asexually propagating conifers in general are described in U.S. Pat. No. 6,372,496 and for slash pine in particular in U.S. Patent Application Publication No. 2004/0203150.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are color photographs showing the new variety of slash pine.

FIG. 1 is a photograph showing ‘CF PS1-3352’ ramet # 2 planted in Nassau, Fla. The picture was taken after seven field growing seasons. The picture shows excellent stem straightness, distinctive long internodes, medium to flat branch angle between the stem and the branches, and medium branch diameter (relative to the size of the stem).

FIG. 2 is a photograph showing ‘CF PS1-3352’ ramet # 1 planted in Nassau, Fla. The picture was taken after seven field growing seasons. The picture shows superiority of growth and stem straightness.

DETAILED BOTANICAL DESCRIPTION

The botanical details of this new and distinct variety of slash pine tree follow. All color descriptions are made in reference to The Royal Horticultural Society (R.H.S.) Colour Chart (2005).

-   Parentage:     -   -   Female parent.—(Unknown) first generation selection made in             Taylor County, Fla.         -   Male parent.—(Unknown) first generation selection made in             Wayne County, Ga.

Compared to unimproved slash pine trees, ‘CF PS1-3352’ is characterized by high growth rate, good resistance to fusiform rust (caused by Cronartium quercuum (Berk.) Miyabe ex Shirai f. sp. fusiforme (Cumm.) Burds. et Snow), good resistance to pitch canker (caused by Fusarium circinatum Nirenburg et O'Donnell), excellent stem straightness, medium crown width, long stem internodes, flat to medium branch angle and medium branch diameter.

-   Average height: 20 ft after 5 field growing seasons -   Maximum height: 23 ft after 5 field growing seasons -   Average trunk diameter at breast height (4.5 feet above the soil     level): 4.1 inches after 5 field growing seasons -   Maximum trunk diameter at breast height (4.5 feet above the soil     level): 4.8 inches after 5 field growing seasons -   Percent stem fusiform rust infection at age 5: 0 -   Percent branch fusiform rust infection at age 5: 0 -   Percent branch and stem fusiform rust infection at age 5: 0 -   Percent dead ramets due to fusiform rust infection at age 5: 0 -   Percent stem fusiform rust infection in the USDA Resistance     Screening Center (Asheville, N.C.) tests after artificial     inoculation with rust spores: 15% (compared to 81% infection in     unimproved seedlings) -   Propagation: Propagated by somatic embryogenesis -   Seeds: None produced at age seven years of age, plants are not yet     mature. Expected seed production by 12-15 years of age. -   Use: High yield industrial plantations -   Average branches per whorl: 4.25 -   Foliage color: Dark green 137A -   Branch bark color: Grey N200C / white N155B -   Trunk bark color: Grey N200C / grey N155B -   Buds color: Yellow brown 167B -   Tree shape: Concial with irregular to compact crown -   Length of needle: 199.84 mm -   Length of sheath: 10.93 mm -   Needle thickness: 0.45 mm -   Needle diameter: 1.1 mm -   Branch diameter: 19.96 mm -   Branch angle: 32.17 degrees -   Branch angle: 5.01 feet -   Branch texture: Rough

Descriptions are mean values from five trees measured at age 9.5 years. Branch data is the mean of branches from the whorl immediately above and below a point 8 feet from the base of each tree. Trees were located in Nassau County, Fla. and measurements were recorded on Oct. 31, 2010.

Although the new variety of slash pine tree possesses the detailed characteristics noted above as a result of the growing conditions prevailing in the test locations, it is to be understood that the variations of the usual magnitude and characteristics incident to changes in growing conditions, irrigation, fertilization, pruning, pest control, climatic variations and the like are to be expected. An example of ‘CF PS1-3352’ can be found at Nassau year 2001 line trial, Nassau county, Fla.

COMPARISON WITH PARENTS BY MICROSATELLITE ANALYSIS

Microsatellite markers were used to generate a unique DNA fingerprint for the variety. Young foliage samples from 5 ramets of PS1-3352 variety and from the parental trees used to make the PS1 cross were collected for DNA fingerprinting. The DNA extraction protocol of Doyle and Doyle (1987) was used after slight modifications. DNA fingerprinting of parents and the PS1-3352 variety was conducted using a set of six microsatellite markers (Echt et al., 2006; Echt et al., 2008). Table 1 shows the sequences and conditions for each primer.

TABLE 1 ID's, sequences and conditions of SSR primers used in slash pine PS1-3352 variety. Ta = primer annealing temperature. LABEL UniSTS GenBank TAIL MgCl2 Primer full ID # accession SEQUENCE (5′-3′) (F/R) (mM) Ta (° C.) PtRIP_0619 513511 BV683091 F:CACGACGTTGTAAAACGAC F 2.5 65 → 55 CAGCTCTCTTAATAGCCTCGG (SEQ ID NO: 1) R:GTTTCTTGCACATAGCAACGCTGAAGA (SEQ ID NO: 2) PtRIP_1040 513556 BV683133 F:CACGACGTTGTAAAACGAC F 2.5 65 → 55 TCAAGGAATTCATTGGAGCC (SEQ ID NO: 3) R:GTTTCTTTTTGGCCATATCAAACCCAT (SEQ ID NO: 4) PtSIFG_0193 516249 BV728742 F:CACGACGTTGTAAAACGAC F 2.5 65 → 55 CCCATGCATCAATTCAAGTT (SEQ ID NO: 5) R:GTTTCTTTGTGCGTGGATATGGAAAAA (SEQ ID NO: 6) PtSIFG_0737 516298 BV728669 F:CACGACGTTGTAAAACGAC F 2.5 65 → 55 GCAAGGGGAATTGCTTATGA (SEQ ID NO: 7) R:GTTTCTTGGGATCGCATCAGCTGTAAT (SEQ ID NO: 8) PtSIFG_1190 516327 BV728679 F:CACGACGTTGTAAAACGAC F 2.5 65 → 55 CAGGTGGCTTGGATTTCATT (SEQ ID NO: 9) R:GTTTCTTTCATTCAAGCGTCCTGCTTA (SEQ ID NO: 10) PtSIFG_4233   516353 BV728685 F:CACGACGTTGTAAAACGAC F 2.5 65 → 55 AGGGAAACCGCGGATTATAG (SEQ ID NO: 11) R:GTTTCTTCCGGAATGAAGATTGCAGTT (SEQ ID NO: 12)

Microsatellite products were detected by M13 tailed primer (Oettling et al., 1995). The amplification products were electrophoresed on 5.5% Long Ranger polyacrylamide gels using a LiCor 4200 automated sequencer (LiCor Inc., Lincoln, Nebr.).

The observed parental genotypes and their expected offspring's genotypes at six studied SSR loci of each family are presented in Table 2. PS1-3352 fingerprint based on 6 loci is presented in Table 3.

TABLE 2 Parental genotypes and their expected offspring's genotypes at six different SSR loci. Genotype Primer Female Male Expected offspring genotypes PtRIP_0619 221/227 223/225 221/223 221/225 227/223 227/225 PtRIP_1040 233/237 217/235 233/217 233/235 237/217 237/235 PtSIFG_0193 256/256 256/256 256/256 PtSIFG_0737 448/460 442/448 448/442 448/448 460/442 460/448 PtSIFG_1190 312/314 312/312 312/312 314/312 PtSIFG_4233 130/136 130/136 130/130 130/136 136/136

TABLE 3 PS1-3352 genotypes at 6 SSR loci. Allelic sizes have LiCor primer tails. PtRIP_0619 PtRIP_1040 PtSIFG_0193 Sample ID Allele1 Allele2 Allele1 Allele2 Allele1 Allele2 PS1-3352 221 223 217 237 256 256 PtSIFG_0737 PtSIFG_1190 PtSIFG_4233 Sample ID Allele1 Allele2 Allele1 Allele2 Allele1 Allele2 PS1-3352 442 448 312 312 130 130

REFERENCES

Auckland, L., T. Bui, Y. Zhou, M. Shepherd and C. Williams. 2002. Conifer Microsatellite Handbook Corporate Press, Raleigh, N.C., USA.

Doyle, J. J. and J. L. Doyle. 1987. A rapid DNA isolation procedure for small quantities of fresh tissue. Phytochemical bulletin 19:11-15.

Echt, C. S., Nelson, C. D., Erpelding, J. E. and Burns, R. 2006. Southern Institute of Forest Genetics, USDA Forest Service Southern Research Station, 23332 Mississippi 67, Saucier, Miss. 39574, USA. On-line genetic database: http://www.ncbi.nlm.nih.gov/unists

Echt, C. S., Saha, S. and Nelson, C. D. 2008. Southern Institute of Forest Genetics, USDA Forest Service Southern Research Station, 23332 Mississippi 67, Saucier, Miss. 39574, USA. On-line genetic database: http://www.ncbi.nlm.nih.gov/unists

Oetting, W. S., H. K. Lee, D. J. Flanders, G. L. Wiesner, T. A. Sellers and R. A. King. 1995. Linkage analysis with multiplexed short tandem repeat polymorphisms using infrared florescence and M13 tailed primers. Genomics 30:450-458. 

1. A new and distinct variety of slash pine tree named ‘CF PS1-3352’ substantially as described and illustrated. 